docs: def _parse_section(token_iter):
      '''take a stream of tokens, and create the tree structure that is defined
      by the s-expressions
      '''
      sexp = []
      for token in token_iter:
          if token == '(':
              new_sexp = _parse_section(token_iter)
              if not _match_section(new_sexp, UNWANTED_SECTIONS):
                  sexp.append(new_sexp)
          elif token == ')':
              return sexp
          else:
              sexp.append(token)
      return sexp